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keith
Posted on Wednesday, April 25, 2001 - 3:37 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I am pretty new to tuning a CB. I did'nt know any better. So now I have a Midland 77-285 with a 225 amp, 18' clear coax, a power mic, and a 4' steel antenna with ground attached. How often do I need to check the Swr and can I do it myself with a in-line meter? And what about the power mic? The 1-10 is that out put strength or loudness. Thanks
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307 (307)
Posted on Thursday, April 26, 2001 - 9:26 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

You only need to check your SWR once a month unless you seem to have trouble. Check your SWR between the radio and the antenna and NOT the radio and the amplifier. Remove the amplifier before testing because the amplifier and cable will change the SWR reading and it may not be correct. The "ground" wire that you attatched can affect the SWR as well because the "wire" acts as an inductor and my cause problems. Adding a ground wire is not always the correct thing to do however in some cases it helps. As for the Power Mic , the 1-10 you are refering to is the output amplification and sets the "loudness" of the audio. Be careful though because setting it up to a "10" may cause squealing.
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Keith
Posted on Thursday, April 26, 2001 - 10:26 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

The local CB shop wants $14 to set or check the SWR. If this is something I need to do monthly I would like to learn how to do it my self. Where can I learn more or read up on it. I thought the swr is checked with a inline meter and adjusted by moving the Antenna up or down to get the lowest reading on the meter.
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307 (307)
Posted on Thursday, April 26, 2001 - 2:09 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Keith , The SWR is set (adjusted) by moving the antenna "stinger" up and down , thus making the length of the antenna change. The reason you should check your SWR each month is because you may have other trouble such as pinched coax or water in the coax connections or a multitude of other problems that "creep" up during the month.
Normally the antenna will not change , however other "things" will. Purchase an SWR meter and you can test it yourself in a matter of minutes.Directions come with the meter for ease of operation and I will be happy to assist you if needed. If you are leary of setting it the first time , have the "CB" shop do it once , then monitor it yourself the rest of the time. You would be surprized at the number of things that affect SWR. Pinched coax , water , loose mounting brackets , shorted PL-259 connecters , bad
jumpers and a multitude of other things. Check it often and your radio will survive for a
long time.
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keith
Posted on Saturday, April 28, 2001 - 1:39 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

okay I ran all new coax(18ft. clear) and run my ground.(cleaned surface well) Check the CB power and ground wire and stripped them and made a new connection to be safe. Everything grounded and clean! I hooked up the new SWR meter and went step by step.When I switch it to Calibration the meter goes to cal on the meter. But when I key the mic it goes back to 1. I try to turn the meters knob so I can get it back to cal but the needle want move!

The next question. I got a palomar 225. the set up is
Power AMP(light) Low/M/High(light) Pre amp(light)
When i tested the power to the amp the power light came on. When I moved the L/M/H no light came on. When I turned the pre amp switch the light in the middle came on. I would think the end light should have came on. Although only power and no coax was connected if this makes a difference. Thanks for all the help. The guy at the local shop was not as nice.
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russell stillwell
Posted on Saturday, April 28, 2001 - 5:54 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

what ever happened to ranger? i see mirage 2950 now are they the same board? any epoxy-is it still a great unit waiting to buy one.
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307 (307)
Posted on Saturday, April 28, 2001 - 10:32 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

You are correct , that is how it should work as far as the lights go. The center one comes on when you "Key" the mic. This tells you you are putting out power. As for the SWR reading , I assume you place the tester from "Cal" to "SWR" when you keyed it the second time? If so , the lower the reading the better. I need a little more information to be exact on your findings.
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keith
Posted on Saturday, April 28, 2001 - 11:03 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Once the mic is keyed the knob want move the needle. This is in the calibration mode.So when the mic is not keyed it is pointing toward cal. But when you key the mic is buries back to 1 on the meter. when it is on 1 in the calibration mode I cannot move the meter needle by moving the adjustment knob.